Path to Herd Immunity Normality : 2021 Outlook of COVID-19 in the US

By: Youyang Gu
Last Updated: March 1, 2021 (First posted December 9, 2020; CDC plots updated daily)

With the availability of the COVID-19 vaccine, we present our best estimate of the path to COVID-19 herd immunity / normality in the United States. Immunity against the SARS-CoV-2 virus comes from two sources: vaccination and natural infection. On this page, we provide the latest COVID-19 vaccine projections and current vaccination progress.

February 24 Update: See our latest thoughts on when to expect a return to normal. Older updates

Last updated - CDC vaccination data plots: Sat, Mar 6 2021 5pm ET
Last updated - Path to Herd Immunity plots: Fri, Mar 5 2021 3am ET

Note: Our infections estimates include all new infected individuals of the SARS-CoV-2 virus, not just those that took a COVID-19 test and tested positive. As of January 2021, we estimate the true number of infected individuals in the US to be roughly 2-4x higher than the reported cases (25-50% detection rate). See our writeup, Estimating True Infections, for a more detailed look into this subject.

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Table of Contents

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Summary

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Relevant Twitter Threads

News / Findings / Thoughts

Weekly Updates

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Disclaimers

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Data

We use vaccination data from the Centers for Disease Control and Prevention (CDC). We upload the raw and adjusted CDC vaccination time series data for download on GitHub. It contains every CDC vaccination update since they started releasing data on Dec 20, 2020. The data is updated daily.

While we release daily past infections estimates for every state and county, we are currently not releasing our vaccination and infections forecasts. This is due to 1) the limitations and noisiness in the existing data 2) the high degree of uncertainty for the future and 3) the reliance on numerous assumptions (outlined below). As a result, we believe these projections are best suited to be viewed in the context of everything outlined on this page, and should best not be used independently. Without all the necessary context/assumptions, the results can easily be misinterpreted.

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Assumptions

The underlying assumptions behind our estimates are presented below:

Basic Assumptions

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Vaccination Assumptions

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Infection Assumptions

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Corollaries

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Helpful Data Sources

Below you will find a list of helpful vaccination data sources and dashboards. While we do not directly use them in our modeling, we highly recommend giving them a look.

Vaccine Rollout Tracker

Vaccine Development Tracker

Questions? Comments? Feedback?

You can reach Youyang Gu via the Contact page.

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Updates